Top frame with locking features

ABSTRACT

A top frame with locking features is provided. The top frame includes four legs having a top surface and a bottom surface. The top frame includes a first interlocking feature in the form of a plurality of protrusions and a second interlocking feature in the form of indented receptacles on the top surface. The plurality of protrusions can be provided proximate a corner of the top frame and the plurality of indented receptacles can also proximate the corner but spaced from the plurality of protrusions. Each corner of the top frame can include a plurality of protrusions and a plurality of indented receptacles. Each occurrence of the plurality of protrusions and the plurality of indented receptacles can alternate about the top surface of the top frame. The bottom surface can also include the same pattern of locking features.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present invention claims priority to and the benefit of U.S.Provisional Patent Application No. 63/129,865 filed Dec. 23, 2020, thecontents of which are incorporated herein by reference and made a parthereof.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

N/A

FIELD OF THE INVENTION

The present invention is generally directed to a top frame withinterlocking features to prevent slippage when shipped in stacks uponother like top frames, and more particularly, to a top frame having aplurality of projections and a plurality of indented receptacles thatalign with indented receptacles and projections, respectively, of a liketop frame.

DESCRIPTION OF THE PRIOR ART

Top frames are used, along with other components—such as pallets, in thetransportation industry to transport goods from one location to another.For example, top frames are part of a primary packaging product used inthe beverage industry to distribute cans (e.g., drawn and ironedaluminum beverage cans) and bottles—typically loaded in stacks separatedby slip sheets on a pallet. The top frame is placed on top of the stackand provides a rigid structure for engaging metal straps or bands, orother similar materials or structures, for securing the entire systemtogether.

The top frames are typically used in a returnable loop system where theyare returned to the manufacturer (after use) stacked together andshipped back in bulk pallet loads. One issue with this system is thatwhen shipped in stacks, the frames tend to slide easily on one anothermaking for a very unstable stack that is difficult to manage.

One solution proposed by Precision Thermoplastics Components, Inc. inU.S. Publication No. 2012/0285851 utilizes a cylindrical pocket thatmates with a ramp that protrudes from the surface of the top frame.However, this system is difficult to align and requires the protrusionto extend a significant amount from the surface of the top frame.

Another solution, proposed by Rehrig Pacific Company, involvesperforming a secondary scuffing operation (i.e., after formation ormolding of the top frame) to apply a texture to the surface andmanipulate the surface friction of the frame (such as that shown forpallets in U.S. Pat. No. 7,216,415). However, this secondary scuffingoperation can be messy and costly. Moreover, the scuffing is lesseffective over time.

The present invention provides a lasting locking mechanism to preventslippage of stacked top frames without requiring strict alignment of theframes, or involve a messy and costly scuffing operation.

SUMMARY OF THE INVENTION

The present invention is directed to a top frame with locking featuresto prevent slippage when stacked on other like top frames. The lockingfeature uses several low profile protruding features that match up witha corresponding mirrored pattern of indented receptacles that locks topframes together, preventing them from sliding off one another. Thelocking features do not have to be perfectly aligned in order tofunction properly. The number of receptacles can be made larger than thenumber of protruding features such that two top frames can be shiftedslightly with respect to each other in the stack and still be lockedtogether. That is, the teeth (i.e., protruding features) can stillengage the receptacles when the top frames are slightly misaligned andshifted off each other for easier stacking. The protruding features andindented receptacles are oriented on each corner (on both sides of eachtop frame) so the top frames can be stacked in any configuration. Thereis no specific top or bottom surface or end to the frames that requireorientation for frames to lock.

In accordance with one aspect of the present invention, a top frame isprovided with interlocking features. The top frame comprises a firstleg, a second leg, a third leg, and a fourth leg to form a generallyrectangular structure or shape with a generally rectangular centralopening. The top frame includes an upper surface and an opposing lowersurface. The top frame also includes a first locking feature in the formof a first plurality of repeating protruding structures positioned at afirst location on the upper surface of the top frame. The top framefurther includes a second locking feature in the form of a firstplurality of repeating indented receptacles at a first location on thelower surface of the top frame. The first locking features of one topframe are designed to mate with or engage the second locking features ofa second like top frame, and so on in a stack of top frames.

The first location of the first plurality of repeating protrudingstructures can be proximate a first corner of the top frame. Similarly,the first location of the first plurality of indented receptacles can beproximate the first corner of the top frame and aligned with the firstplurality of repeating protruding structures.

The first plurality of repeating indented receptacles can be a mirroredpattern of the first plurality of repeating protruding structures. Thatis, the receptacles can have a conforming shape to that of theprotrusions. In some preferred instances, the number or amount of thefirst plurality of repeating indented receptacles is greater than atotal number or amount of the first plurality of repeating protrudingstructures. In these instances, the top frames can be offset withrespect to each other and still be able to accommodate all of theprotrusions to lock the frames and prevent slippage.

The top frame can also comprise a second plurality of repeatingprotruding structures positioned proximate a second corner of the topframe on the lower surface of the top frame and a second plurality ofrepeating indented receptacles positioned proximate the second corner ofthe top frame on the upper surface of the top frame and aligned with thesecond plurality of repeating protruding structures. In fact, each ofthe top surface and the lower surface can have alternating sets of aplurality of protrusions and a plurality of receptacles at each corner.

The first plurality of repeating protruding structures can have asaw-tooth cross-sectional shape. Similarly, the first plurality ofindented receptacles can have a saw-tooth cross-sectional shape.

The top frame can be formed from a molded plastic in two pieces. Eachpiece includes a flat outer surface and a plurality of ribs extendingfrom the outer surface. The two pieces are welded together so that theribs extend between each of the flat outer surfaces.

In accordance with another aspect of the invention, a top frame withinterlocking features comprises a first leg having a first end and asecond end, a second leg connected at a first end to the second end ofthe first leg, a third leg connected at a first end to a second end ofthe second leg and a fourth leg connected at a first end to a second endof the third leg and connected at a second end to the first end of thefirst leg. The first leg, second leg, third leg and fourth leg have anupper surface and a plurality of ribs extending downward from the uppersurface. The top frame includes a first plurality of ridges extendingupward from the upper surface at a first location and a first pluralityof receptacles extending downward from the upper surface at a secondlocation. The first location can be proximate a first corner of the topframe formed by the first leg and the second leg, and the secondlocation can be proximate the first corner and spaced from the firstlocation.

Additionally, the top frame can include a second plurality of ridgesextending upward from the upper surface proximate a second corner formedby the second leg and the third leg and a second plurality ofreceptacles extending down from the surface proximate the second cornerand spaced from the second plurality of ridges. The first plurality ofridges can have a saw-tooth cross-sectional shape and the firstplurality of receptacles can also have a saw-tooth cross-sectionalshape.

The top frame can include a second component having a fifth leg having afirst end and a second end, a sixth leg connected at a first end to thesecond end of the fifth leg, a seventh leg connected at a first end to asecond end of the sixth leg and an eighth leg connected at a first endto a second end of the seventh leg and connected at a second end to thefirst end of the fifth leg. Like the first component described above,the fifth leg, sixth leg, seventh leg and eighth leg have a lowersurface and a plurality of ribs extending from the lower surface. Theribs from the lower surface are welded to the plurality of ribsextending downward from the upper surface. The lower surface can includea first plurality of ridges extending downward from the lower surface ata first location and a first plurality of receptacles extending upwardfrom the lower surface at a second location.

Other features and advantages of the invention will be apparent from thefollowing specification taken in conjunction with the following Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

To understand the present invention, it will now be described by way ofexample, with reference to the accompanying drawings in which:

FIG. 1 is an upper perspective view of two stacked top frames havinginterlocking features in accordance with the present invention;

FIG. 2 is an enlarged perspective view of a corner portion of thestacked top frames of FIG. 1;

FIG. 3 is an enlarged perspective view of a plurality of protrusions inaccordance with an aspect of the present invention;

FIG. 4 is an enlarged perspective view of a plurality of indentedreceptacles in accordance with an aspect of the present invention;

FIG. 5 is a cross-sectional view of the locking features of a first topframe and a second frame in a first configuration;

FIG. 6 is a cross-sectional view of the locking features of a first topframe and a second frame in a second configuration; and,

FIG. 7 is a perspective view of a lower portion of half of a top frame.

DETAILED DESCRIPTION

While this invention is susceptible of embodiments in many differentforms, there is shown in the drawings and will herein be described indetail preferred embodiments of the invention with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention and is not intended to limit the broadaspect of the invention to the embodiments illustrated.

FIG. 1 is a perspective view of an upper top frame 10 stacked on a lowertop frame 10′ in accordance with the present invention (only the veryedge of the lower top frame 10′ is visible in this Figure). The uppertop frame 10 is generally rectangular with slightly rounded corners andincludes a first leg 12, a second leg 14, a third leg 16 and a fourthleg 18 (the lower top frame 10′ is identical to the upper top frame 10).The legs 12, 14, 16, 18 are connected at their ends to form four cornersand define a generally rectangular central opening 20 (in someembodiments, the top frames can include cross beams and other structuresextending between the legs in the opening). The top frame 10 includes agenerally planar upper surface 22 and a corresponding lower surface(which, in the configuration of this Figure would be in contact with theupper surface of the lower top frame 10′). The top frame 10 ispreferably formed from a molded plastic in two parts that are weldedtogether to form a rigid member for facilitating transportation of goodssuch as stacks of beverage cans or bottles on a pallet. The frame allowsfor metal bands or straps to be tensioned around the top frame, palletand stacks of beverage cans or bottles (or other goods transportedsupported on the pallet).

Each corner of the top frame 10 includes a first locking feature in theform of a plurality of repeating protrusions 24 extending upward fromthe top surface 22 of the top frame 10, and a second locking feature inthe form of a plurality of repeating indented receptacles 26 extendingdownward from the planar portion of the upper surface 22. The firstlocking features and second locking features are arranged so that theyalternate around the upper surface 22 of the top frame 10. This meansthat each leg has one of the plurality of protrusions 24 at one end andone of the plurality of indented receptacles 26 at the other end. Whileonly the top surface 22 is shown in FIG. 1, a bottom surface of the topframe 10 will include essentially the same pattern of alternating firstlocking features 24 and second locking features 26 proximate the cornersof the top frame 10.

The plurality of repeating protrusions 24 and the plurality of repeatingindented receptacles 26 are shown in greater detail in FIGS. 3 and 4,respectively. In the example provided in FIG. 3, the plurality ofrepeating protrusions 24 includes four generally triangular (incross-section) protrusions 28 in a row slightly spaced from one anotherby flat segments 30. Similarly, the plurality of repeating indentedreceptacles 26 includes six receptacles 32 where each receptacle 32 isconfigured to mate with or receive one of the protrusions 28.

As evident in FIGS. 3 and 4 there is a greater number of receptacles 32in each plurality of repeating indented receptacles 26 than protrusions28 in each plurality of repeating protrusions 24. This allows for aslight misalignment of the two structures and still have an interlockbetween the top frames. For example, as illustrated in thecross-sectional view of FIG. 5, the four protrusions 28 on the lower topframe 10′ are positioned in the middle receptacles 32 of the upper topframe 10 such that there is an empty receptacle 34 on each side of theplurality of protrusions 24. In the cross-sectional view of FIG. 6, thebottom top frame 10′ is in a slightly different position with respect tothe upper top frame 10 such that both empty receptacles 34 are at oneend of the four protrusions 28. While the number of protrusions andreceptacles are shown as being four and six, respectively, each could bemore or less as desired for a particular size of the top frame or aparticular size of the protrusions/receptacles.

In addition to allowing some misalignment between the top frames in viewof the additional receptacles, the size of the protrusions with respectto the receptacles can be chosen to provide for misalignment along theirlengths. That is, the length of each protrusion 28—from one end to theother—can be significantly less than the length of each receptacle32—from one end to the other—providing room for misplacement along thelength direction.

As illustrated in FIGS. 5 and 6, the plurality of protrusions 24 and theplurality of indented receptacles 26 each have a saw-tooth (or aslightly spaced saw-tooth) configuration. The cross-sectional design canalso be chosen to have other similar repeating configurations.

Each of the top frames 10 in accordance with the present invention areformed from two identical halves that are welded together. FIG. 7 showsthe bottom of a half 36 of a top frame 10 (the other surface—not shownhere—would be identical to surface 22 as illustrated in FIG. 1). Thehalf 36 includes a plurality of ribs 38 that extend from a planarsurface. The ribs 38 are welded to ribs 38 of another half 36 to form acomplete top frame 10 having an upper surface and an identical lowersurface. In some instances, only a half 36 of the top frame may beneeded. In which case two can be stacked on each with the supportsurfaces facing each other to engage the locking features.

As used herein, directional terms—such as top, bottom, upper, lower,etc.—are used with respect to the top frames, or portions thereof, asshown or positioned in the drawings, and are not meant to limit thescope of the invention or require the top frame to remain in thatposition. For example, an upper surface would still exist if the topframe was moved upside down.

Many modifications and variations of the present invention are possiblein light of the above teachings. It is, therefore, to be understoodwithin the scope of the appended claims the invention may be protectedotherwise than as specifically described.

I claim:
 1. A top frame with interlocking features comprising: a firstleg; a second leg; a third leg; a fourth leg, wherein the first leg,second leg, third leg and fourth leg form a generally rectangular shapehaving an upper surface and an opposing lower surface; a first pluralityof repeating protruding structures positioned at a first location on theupper surface of the top frame; and, a first plurality of repeatingindented receptacles at a first location on the lower surface of the topframe.
 2. The top frame of claim 1 wherein the first location of thefirst plurality of repeating protruding structures is proximate a firstcorner of the top frame.
 3. The top frame of claim 2 wherein the firstlocation of the first plurality of indented receptacles is proximate thefirst corner of the top frame and aligned with the first plurality ofrepeating protruding structures.
 4. The top frame of claim 3 wherein thefirst plurality of repeating indented receptacles is a mirrored patternof the first plurality of repeating protruding structures.
 5. The topframe of claim 3 further comprising: a second plurality of repeatingprotruding structures positioned proximate a second corner of the topframe on the lower surface of the top frame; and, a second plurality ofrepeating indented receptacles positioned proximate the second corner ofthe top frame on the upper surface of the top frame and aligned with thesecond plurality of repeating protruding structures.
 6. The top frame ofclaim 1 wherein the first plurality of repeating protruding structureshas a saw-tooth cross-sectional shape.
 7. The top frame of claim 1wherein a total amount of the first plurality of repeating indentedreceptacles is greater than a total amount of the first plurality ofrepeating protruding structures.
 8. The top frame of claim 1 wherein thetop frame includes a plurality of ribs extending from the upper surfaceto the lower surface.
 9. The top frame of claim 1 wherein the first leg,second leg, third leg and fourth leg define a generally rectangularopening therebetween.
 10. The top frame of claim 5 further comprising: athird plurality of repeating protruding structures positioned proximatea third corner of the top frame; and, a first plurality of repeatingindented receptacles positioned proximate the third corner of the topframe.
 11. The top frame of claim 10 further comprising: a fourthplurality of repeating protruding structures positioned proximate afourth corner of the top frame; and, a fourth plurality of repeatingindented receptacles positioned proximate the fourth corner of the topframe.
 12. The top frame of claim 2 further comprising a secondplurality of repeating indented receptacles on the upper surfaceproximate the first corner and proximate the first plurality ofrepeating protruding features.
 13. The top frame of claim 1 formed froma molded plastic.
 14. A top frame with interlocking features comprising:a first leg having a first end and a second end; a second leg connectedat a first end to the second end of the first leg; a third leg connectedat a first end to a second end of the second leg; a fourth leg connectedat a first end to a second end of the third leg and connected at asecond end to the first end of the first leg; the first leg, second leg,third leg and fourth leg having an upper surface; a first plurality ofridges extending upward from the upper surface at a first location; and,a first plurality of receptacles extending downward from the uppersurface at a second location.
 15. The top frame of claim 14 furthercomprising a plurality of ribs extending downward from the top surface.16. The top frame of claim 14 wherein the first location is proximate afirst corner of the top frame formed by the first leg and the secondleg, and the second location is proximate the first corner and spacedfrom the first location.
 17. The top frame of claim 16 furthercomprising: a second plurality of ridges extending upward from the uppersurface proximate a second corner formed by the second leg and the thirdleg; and, a second plurality of receptacles extending down from thesurface proximate the second corner and spaced from the second pluralityof ridges.
 18. The top frame of claim 14 wherein the first plurality ofridges has a saw-tooth cross-sectional shape, and the first plurality ofreceptacles has a saw-tooth cross-sectional shape.
 19. The top frame ofclaim 15 further comprising: a fifth leg having a first end and a secondend; a sixth leg connected at a first end to the second end of the fifthleg; a seventh leg connected at a first end to a second end of the sixthleg; an eighth leg connected at a first end to a second end of theseventh leg and connected at a second end to the first end of the fifthleg; the fifth leg, sixth leg, seventh leg and eighth leg having a lowersurface and a plurality of ribs extending upward and welded to theplurality of ribs extending downward from the upper surface; a firstplurality of ridges extending downward from the lower surface at a firstlocation; and, a first plurality of receptacles extending upward fromthe lower surface at a second location.
 20. The top frame of claim 14wherein the top frame is formed from a molded plastic.